Tom Boger is Sr. Director of Mac Product Marketing at Apple. He's worked on projects including the original iMac. Earlier this week, he took to the Apple keynote stage to introduce the new Mac mini....

Well, I did. Challenging Apple about having a more and more complex product line which translates in a more difficult buying decision... would have been interesting... we are far from the simple model SJobs used to talk about...

In fairness, Rene did ask exactly the question you refer to re: MacBook vs. MacBook Air, even pointing to the same quadrant. I agree with you Tom's answer wasn't very clear, but I don't think continuing to push the point would have led to a clearer answer.

Yeah, that's how he explained it. But until yesterday, the Air brand was clearly positioned below the regular MacBook, it was sort of the iPhone SE / iPhone XR of the MacBook line-up. Is it now permanently in the middle? Or only until next MacBook spec bump?

Middle is horizontal. Below is vertical. It is middle. It is not below.
Apple has customers that will pay a premium for max portability.
MacBook is higher than Air, just in the opposite way than the Pro.